Interesting and beautiful picture.
However, if it is true that the dynamic range of that particular scene was "brightness range of over 10,000 to 1", that means LOG(10000)/LOG(2)=13,29 f-stops of DR. I cannot see then any need for 28 captures. Just 3 of them, 3 f-stops apart would have sufficed with any of our digital cameras.
Looking at the texture of the moon compared to the solar radiance I think the 10000:1 ratio is quite wrong, and the real contrast was higher.
I wonder if the great number of images has something to do with the limitations of Photoshop's Merge to HDR. I often find when attempting to merge 3 images which are 3-4 stops apart that I get strange discolorations in the sky. This usually occurs when the longest exposure has a severly blown out sky (for example) and the shortest exposure has a correctly exposed sky. In such circumstances, I usually have to discard the longest exposure, which provides the best detail in the shadows, and content myself with a more modest DR increase of 1.5 to 2 stops by merging just the two shorter exposures.
In other words, it's better to merge a larger number of images with a smaller exposure difference. I wish my camera could autobracket 5 exposures rather than just 3.
I believe your noise reduction method has addressed this problem